Hi fuzzyrider,
There are now and then people here that complain about similar issues concerning DMT experiences. It seems some people respond this way to it, especially the first time. I could make wild assumptions as to what it is in their psyche that causes this, but I doubt it would be helpful. It's something you have to find out for yourself.
What I can tell you with reasonable certaintly is that there is no scientific evidence for any phisiological damage that DMT causes. It does not seem to have lasting physiological effects at all. This means that you have certainly not broken your brain. What you are experiencing is psychological.
This can mean a variety of things. Psychology is intricately related to your neurochemistry and a dmt experience might have disrupted the balance of this momentarily. If you are not using other substances or medication it should re-establish itself within a few days.
What certainly happens with a DMT experience is that our thoughts and world-views can get quite mixed up, jumbled, shattered and obliterated. Parts of the subconscious might surface, repressed fears or thoughts might be let lose, etc. In other words, the structure of your psyche might be affected and this may cause the negative feelings you are experiencing at the moment. One very good advice was given before: don't resist the feelings that surface. Fighting off fear or other emotions is a good way to give them more power over us. A good way to deal with these things I've found is to aknowledge their existence without identifying with them: I am not my fear, I am not this thought, this too shall pass.
Another very important thing to do is to integrate the experience - the DMT as well as the things that you are going through now. You can do this by writing or by talking about it with other people, by painting or by meditating, by contemplating while walking through the woods, etc. But do it. For me writing and walking/moving work best. Sometimes going for a long swim will also help, especially when I'm feeling depressed or anxious. Try something that makes you feel good. Try also relaxing, make some time for a spaa in your bathtub, go get a massage, go to a sauna, etc.
Stop smoking cannabis for a while, if you are.
eat well
and try to heal whatever wound you have opened or re-opened.